BR112020012803A2 - polyester material for packaging - Google Patents

Abstract

White goniochromatic packaging item. The wall of the package contains a composition useful for blocking light in the spectrum bands between about 200 nm to about 1200 nm. The composition has polyester, polymethylpentene and a pigment for light dispersion. The composition optionally includes at least one other dye. Each of polymethylpentene and the light dispersion pigment comprises about 0.1 to about 0.5 weight percent of the wall. Polyester and polymethylpentene are immiscible and when subjected to orientation stress the composition produces an article for goniochromatic packaging.

Description

Invention Patent Descriptive Report for "POLYESTER MATERIAL FOR PACKAGING".

CROSS REFERENCE TO RELATED ORDER

[001] This application claims the priority and benefit of United States Provisional Patent Application Serial No. 62 / 611,713, entitled "White Polyester Packaging Material" filed on December 29, 2017. This application also claims the priority and benefit United States Provisional Patent Application Serial No. 62 / 764,783, entitled "White Polyester Packaging Material" filed on August 16, 2018. Each application is incorporated herein by reference in its entirety.

FIELD

[002] The present invention relates to packaging. In particular, the invention relates to a packaging with a high luminosity value, a high blockage of light, a low percentage of additives and a goniochromatic appearance (uniform color across all viewing angles).

BACKGROUND

[003] In the field of packaging, plastic has replaced other materials, such as glass. This replacement minimizes breakage, reduces weight and reduces the energy consumed in manufacturing and transportation.

[004] Attracting consumers to buy containers of individual size or family size includes the trademark and the commercial presentation. Among the valuable elements of the commercial presentation is the color of the container. Among the valuable elements of a trademark is consistent color visibility. For certain products, such as milk, a clear or shiny white container is desired.

[005] The luminosity can be defined within the CIELAB color space, which describes mathematically all the perceivable colors in three dimensions: L * for luminosity, a * for green-red and b * for blue-yellow. Figure 1 represents the CIELAB color scale. In the CIELAB color space, the L * axis is oriented from top to bottom. The maximum for L * is 100, which would be a perfect reflection diffuser (ie the brightest white). The minimum for L * would be 0, which would be a perfect absorber (that is, the darkest black). the positive * is red. the negative * is green. b * positive is yellow. b * is blue.

[006] One of the most important attributes of the CIELAB model is the independence of the device. This means that colors are defined regardless of the nature of the creation or the device on which they are displayed. The L * value of the CIELAB color scale can be obtained using any CIELAB color measurement instrument and is calculated using the formula: where Y is the tristimulus value CIE and Yn is the tristimulus value of the illuminant. The CIELAB model allows the quantification of how bright a product really is. Brightness is usually achieved by adding highly reflective and minimally absorbing components, for example, titanium dioxide (TiO2).

[007] The goniochromatic packages maintain color and appearance in all angles of view. Goniochromatic packaging is beneficial for its uniform color consistency and brand recognition, regardless of the consumer's viewing position. On the other hand, the gonio-apparent packaging shows a color difference through the viewing angles. Metallic or pearly effects are gonio-apparent. Although metallic or pearly effects can attract attention, they can lead to reduced brand recognition and non-uniformity of color.

[008] Mixtures separated by phase, as illustrated in Figure 3, result when immiscible polymers are mixed. However, when these phase-separated mixtures are subjected to orientation stresses (for example, blow molding, biaxial sheet orientation, monoaxial elongation, thermoforming or fiber spinning), the spheres of the minor immiscible component flatten out. The problem is that such immiscible components may not flatten out entirely, leading to overlapping internal gaps within the structural polymer, as illustrated in Figure 4. These gaps create an infinity of light scattering surfaces that reflect light in an uneven way, resulting in in a gonio-apparent effect (for example, pearly or metallic appearance), where the color difference in the viewing angles changes by more than 10 DECMC units

[009] The gonio-appearance can be measured with a multi-angle spectrophotometer, such as an MA-T12 from X-Rite. ASTM E2175 describes standard practice for specifying the geometry of multi-angle spectrophotometers. The color difference, as calculated using CIELAB DECMC, between the near and far specular viewing angles can be used to quantify the gonium-appearance magnitude. Using a 45 ° incident light source and measuring near specular (15 °) and distant specular (110 °) color, the color difference demonstrates the change in appearance at various viewing angles. Figure 2 shows such a measurement for gonio-appearance. For such measurement, a difference of more than 10 DECMC units is significant and indicates gonium-appearance. A difference less than 10 DECMC units is not significant and indicates a goniochromatic appearance.

[0010] A barrier against light is also desirable because it is necessary to obscure the contents of a package or to prevent degradation of the quality of the packaged product during the period of time between packaging and consumption. Exposure to light can cause unwanted changes in packaged products. It is difficult to avoid this degradation when the product is sensitive to light radiation. In milk, for example, light has harmful photochemical and ionizing effects. Specifically, riboflavin is photo-degraded when exposed to light between 200 nm and 520 nm. This degradation adversely affects the taste and odor of milk.

[0011] A light barrier prevents certain wavelengths of light from passing through the walls of the package. This can be achieved through reflection or absorption, which avoids harmful effects on the content contained in the packaging. However, typical methods of achieving a light barrier are associated with performance tradeoffs in other critical areas of the packaging.

[0012] A bright white color would reflect almost all light, thus protecting the product from further degradation. Previously, to obtain a shiny white container, dyes or opacifiers were added. Such additional dyes or opacifiers added to the cost of the container and may result in a swirling appearance (ie, the dye and / or opacifier appear not to have dispersed completely within the composition), which can have a negative impact on perception of the product by the consumer. Opacifiers can also lead to reduced physical properties due to the high pigment content, less recyclability and less gloss. For blow-molded PET bottles or thermoformed parts, high levels of opacifiers lead to difficulties in reheating preforms due to the high reflectivity of infrared light.

[0013] To overcome high reflectivity, absorbent pigments and / or dyes are commonly used to increase the light barrier and reduce the total dye content. However, adding absorbent pigments also reduces the lightness of a package. Until now, creating a lighter packaging with a high light barrier required sacrificing luminosity, light barrier or high load levels (affecting cost, physical properties, brightness, recycling).

[0014] US Patent 4,377,616 describes appearance of glossy satin, opaque film compositions and method of preparing them. US patent 5,089,309 describes a semitransparent resin container with pearly luster. US Patent 4,368,295 describes films of polyester compositions and olefin polymers. US Patent 3,640,944 describes a modified polyester film for perforated tapes. US Patent 8,575,296 describes polyester articles that have a simulated metallic or pearl appearance. EP 2035209B1 describes a preform and a container for radio-sensitive products and a method for their manufacture. US publication No. 2017 / 0306143A1 describes a light barrier composition and articles that comprise it.

[0015] The references identified above describe articles with a pearly appearance, also described as glossy, pearly or metallic, which is not desirable. In addition, these references show that the use of incompatible polymers, such as polypropylene, must be used at loading levels above 5% and have no synergistic effect when used in combination with a pigment to disperse light. In summary, such references do not describe how to create a goniochromatic appearance with a constant color over a wide range of viewing angles and synergistically improve the light barrier, allowing for a reduced additive load, higher L * and a brighter and whiter with low levels of incompatible polymer loading.

[0016] Thus, a low-cost goniochromatic composition produced from immiscible polymers is necessary. It is desirable that the composition has an anti-swirling behavior that provides whiteness and lightness without the typical compensations in the light barrier or any other properties such as physical properties, the ability to be recycled, brightness or the ability to reheat.

SUMMARY

[0017] It is known that white articles made with materials separated by phases have a pearly or pearly effect (that is, a gonio-apparent aspect). It has been found that the use of polymethylpentene and a light scattering pigment has an unexpected synergistic effect, even at very low levels of addition of such components and creates a wall in the package with a goniochromatic appearance and excellent light blocking properties.

[0018] Such wall includes a polyester combined with a oriented polymethylpentene and a pigment for light dispersion. About 0.1 to about 5.0 weight percent of the wall is polymethylpentene and about 0.1 to about 5.0 weight percent of the wall is a light-dispersing pigment. The ratio of polymethylpentene to the pigment that scatters light on the wall is about 5: 1 to about 1: 5. In addition, the wall is goniochromatic.

[0019] The combination of a pigment for the dispersion of light with polymethylpentene synergistically increases the reflection of light, which consequently intensifies the barrier against light. Since the synergistic increase in light reflection does not occur until after orientation (for example, blow molding), L * and the whiteness index may be lower before orientation. Due to the reduced amount of dyes and / or opacifiers, the composition exhibits anti-swirling behavior, as a lower concentration may be easier to disperse. As a result, the described composition provides a low cost composition with anti-swirling behavior that requires little or no opacifier or dye to produce a shiny white goniochromatic package.

[0020] Without a light-scattering pigment, a package with light-scattering surfaces similar to an elongated plate, will have a gonio-apparent appearance, showing a large color change through various viewing angles and may be unrecognizable, depending on lighting conditions and the viewer's position. The addition of a light-dispersing pigment to the structural polymer (eg, polyester) and to the polymethylpentene composition surprisingly eliminates gonium-appearance with only a small amount of light-dispersing pigment, as low as 0.1%.

[0021] In certain embodiments of the invention, the light scattering pigment is selected from the group consisting of aluminum trihydrate (Al (OH) 3), titanium dioxide (TiO2), barium sulfate (BaSO4), sulfide zinc (ZnS), mica, ultramarine blue (PB 29), metal oxide particles, such as yellow pigment 53 (PY 53), red iron oxide (PR 101), black iron oxide (PB1k 11), Chromium Green- Black Hematite (PG 17), cobalt aluminate (PB 28) and their combinations.

[0022] Another effect of the reduced amount of pigments or dyes is the better physical properties. Dyes and / or opacifiers can contribute to the degradation of the polymer, bringing moisture and increasing the shear stress in the processing of the polymer. Additives also reduce the total amount of structural polymer that can contribute to physical properties. The degraded polymer can result in decreased physical properties, such as maximum load, tensile strength or cracking due to environmental stress.

[0023] Another effect of the reduced amount of dyes and / or opacifiers is the improved reheating performance. Dyes and / or opacifiers that are typically used to create white packaging reflect light, including the infrared light often used to reheat packaging materials for thermoforming or blown bottles. With less reflected IR light, a structural polymer will absorb more efficiently and reheat more evenly. Since polymethylpentene creates reflection after orientation, the color and appearance of an oriented sample will be different from an unoriented (that is, amorphous) sample.

[0024] Another effect of the reduced amount of dyes and / or opacifiers is the improved or maintained brightness. Dyes and opacifiers can affect the smoothness of the surface when used at very high loads, resulting in a less shiny appearance. Reducing the amount of dyes maintains the smoothness of the surface and a highly shiny appearance.

[0025] Another effect of the reduced amount of dyes and / or opacifiers is improved recycling. Dyes and / or opacifiers can be considered contaminants in the recycling stream. As polymethylpentene does not show strong reflectivity until after orientation, recycling in an unguided article has less impact on the recyclability than other pigments and / or dyes.

[0026] In certain embodiments of the present invention, the wall of the package may contain a second pigment or a dye, separate from the pigment for light dispersion, in which the second pigment is selected from the group consisting of: dyes, pigments, thermochromic pigments , fluorescent pigments, pearlescent pigments and metallic pigments or a combination thereof.

[0027] In certain embodiments of the present invention, the gonio-appearance of the wall is less than 10 units, measured as DECMC with a light source incident at 45 ° between 15 ° of close specular reflection and 110 ° of distant specular reflection.

[0028] In certain embodiments of the present invention, polyester is selected from the group consisting of: polyethylene terephthalate (PET), PET copolymers, polybutylene terephthalate (PBT), PBT copolymers, polylactic acid (PLA), poly-trimethylene terephthalate (PTT), polyethylene naphthalate (PEN), polyethylene furanoate (PEF), polycyclohexylene dimethylene terephtate (PCT), PCT copolymers, sulfonated polyesters, polyester copolymers, polycaprolactone (PCL), polyester -hydroxyalkanoate (PHA).

[0029] In certain embodiments of the present invention, polymethylpentene comprises: about 0.1 to about 3.0, about 0.2 to about 2.0 or about 0.2 to about 4.0 percent by weight of the wall.

[0030] In certain embodiments of the present invention, the ratio of polymethylpentene to light scattering pigment on the packaging wall is: about 4: 1 to about 1: 4 or about 3: 1 to about 1: 3 .

[0031] In certain embodiments of the present invention, the light scattering pigment is titanium dioxide (TiO2).

[0032] In certain embodiments of the present invention, the wall has a light barrier for wavelengths ranging from about 200 nm to about 1200 nm, more than: about 90, about 95, about 98 , about 99 or about 99.5 percent. In other embodiments, the wall has a light barrier for wavelengths ranging from about 400 nm to about 700 nm, more than: about 90, about 95, about 95, about 98, about 99 or about 99.5 percent.

[0033] In certain embodiments of the present invention, the L * value of the wall according to the CIELAB color space is greater than: about 75, about 80 or about 85.

[0034] In certain embodiments of the present invention, the wall is a single layer container wall. In other embodiments, the wall is a multi-layered container wall, wherein at least one layer includes a polyester, a oriented polymethylpentene and a light-dispersing pigment.

[0035] In certain embodiments, additional dyes (ie, a separate component of the light scattering pigment) are added to the wall, including: dyes, special effect pigments or other additives, such as UV absorbers, antioxidant stabilizers, dispersants, waxes, non-slip additives, other polymers or other components, such as, for example, thermochromic pigments, fluorescent pigments, pearlescent pigments and metallic pigments.

[0036] In certain embodiments of the present invention, polymethylpentene is oriented by injection blow molding, extrusion blow molding, film or sheet with uniaxial or biaxial orientation, blown film, thermoforming or fiber spinning. There are no specific guidance limits. In general, a higher orientation leads to higher reflective surfaces and greater blockage of light.

[0037] Finally, a method of producing the packaging wall is described, whereby a polyester, a polymethylpentene and a light scattering pigment are combined to produce a mixture of about 0.1 to about 5.0 percent by weight of polymethylpentene and about 0.1 to about 5.0 percent by weight of the light scattering pigment. In addition, the ratio of polymethylpentene to pigment for light scattering is about

5: 1 to about 1: 5. The wall is then produced by subjecting the mixture to orientation stress, thereby orienting the structural polymer.

[0038] In certain embodiments, the density of the mixture before being subjected to the orientation stress is equal to or less than that of polyester. In other embodiments, the density of the wall after being subjected to orientation stress is equal to or less than that of polyester.

[0039] In a non-limiting modality, a product can be added to a container with walls that have a oriented polyester, polymethylpentene and a pigment for light dispersion and, optionally, another pigment and / or dye. The container can then be sealed.

[0040] It should be understood that the previous general description and the following detailed description are exemplary, but are not restrictive of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a diagram of the CIELAB L *, a *, b * color space;

[0042] Figure 2 is a gonio-apparent color measurement diagram.

[0043] Figure 3 is an example of a mixture of immiscible polymers; and the

[0044] Figure 4 is an example of a mixture of immiscible polymers subjected to orientation.

DETAILED DESCRIPTION

[0045] The modalities described here include compositions that are useful in the manufacture of bright white packaging. The embodiments include a packaging wall comprising, consisting essentially of or consisting of: a polyester;

between about 0.1 to about 5.0 weight percent of polymethylpentene; and between about 0.1 to about 5.0 weight percent of light scattering pigment, where the ratio of polymethylpentene to light scattering pigment is from about 5: 1 to about 1: 5, and the wall is goniochromatic. Once subjected to biaxial orientation tension (for example, blow molding), the packaging wall is bright white, having an L * value according to the CIELAB color scale greater than about 75. In addition, in some modalities , the composition has a light barrier greater than 90% for light within the wavelength between about 200 nm and about 1200 nm. Polyester Structural Polymer

[0046] As used herein, the term "structural polymer" refers to a polymeric material that comprises most of the composition and that provides most of the mechanical properties for an article such as, for example, a plastic container. Preferably, the structural polymer is a polyester polymer. The structural polymer is referred to as reference No. 100 in Figures 3 and

4.

[0047] Any polyester is a candidate for use in the present invention. The formation of a polyester from a mono-alcohol or a polyol and an acid or its ester encompasses many different types of polyesters suitable for use in this invention. Monomeric units can be reactions formed by aliphatic moieties, aromatic moieties or both. Desirably, polyester is transparent or semi-transparent.

[0048] Non-limiting examples of polyesters include terephthalates, terephthalates glycols, lactides, (hydroxy) alkanoates, copolyesters of terephthalic acid residues, 2,2,4,4-tetramethyl-1,3-cyclobutanediol and 1,4-cyclo- hexanedimethanol, etc. or their combinations.

[0049] In addition, homopolyesters or copolyesters, such as homopolymers and copolymers of terephthalic acid and isophthalic acid can be used. Linear polyesters can be produced by condensing one or more dicarboxylic acids or a lower alkyl diester, for example, dimethyltereftalate, terephthalic acid, isophthalic acid, phthalic acid, 2,5-, 2,6- or 2,7- naphthalene dicarboxylic acid, succinic acid, sebacic acid, adipic acid, azelaic acid, bibenzoic acid and hexahydroterephthalic acid or bis-p-carboxyphenoxyethane, with one or more glycols, for example, ethylene glycol, pentyl glycol and 1,4-cyclo- hexanedimethanol.

[0050] Of these various polyester candidates, due to commercial availability, terephthalates, such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT), lactides, such as polylactic acid (PLA), and hydroxyalkanoates , such as polyhydroxybutyrate (PHB) or polyhydroxybutyrate-co-valerate (PHBV), are desirable for use. PET is preferred due to its ubiquity and cost, although PLA and PHBV are emerging as thermoplastic polyesters of biological origin that can supplant PET in some situations. In some embodiments, PET can be mixed with other polyesters. Polymethylpentene

[0051] As used herein, "polymethylpentene" refers to a thermoplastic homopolymer or copolymer that consists mainly of 4-methyl-1-pentene units. Polymethylpentene can include copolymers with 1-decene, 1-hexadecene, 1-octadecene or combinations thereof. With reference to Figures 3 and 4, polymethylpentene is referred to as reference No. 110 and is incompatible with the structural polyester polymer 100 and constitutes a minor dispersed phase. In a non-limiting embodiment, polymethylpentene 110 is present between about 0.1 weight percent and about 5.0 weight percent of the composition.

[0052] When present on a packaging wall, polymethylpentene 110 is present at about 0.1 weight percent and about 5.0 weight percent, or between about 0.1 to about 3.0 percent by weight, or from about 0.2 to about 2.0 weight percent, or from about 0.2 to about 4.0 weight percent, or from about 0.1 to about 0.5 percent by weight, or from about 0.1 to about 0.7 percent by weight, or from about 0.1 to about 1.0 percent by weight, or from about 0.5 to about 2, 0 weight percent of the wall weight.

[0053] With reference to Figures 3 and 4 and without being limited by any particular theory, it is considered that when a structural polymer 100 with dispersed phases of polymethylpentene 110 is subjected to orientation stress (for example, blow molding), the The rigidity and surface tension of the polymethylpentene 110 allows structural polymer 100 to flow around polymethylpentene 110. Polymethylpentene 110 maintains its shape, within a reasonable degree of tolerance, resulting in the formation of voids 120 within structural polymer 100. The light-dispersing pigments disperse within structural polymer 100, even though they were dispersed at the same time in polymethylpentene 110. light-dispersing pigments disperse light in several directions and interrupt the gonioparent aspect of empty spaces 120 to create a goniochromatic appearance. Thus, polymethylpentene 110, when combined with light-dispersing pigments in a composition employed to form a container by an orientation process (for example, blow molding) gives a goniochromatic appearance to a container wall once oriented.

[0054] In some embodiments, the packaging compositions and walls described in this document are free of polypropylene.

Light Dispersing Pigment

[0055] As used herein, "light scattering pigment" refers to any inclusion in structural polymer 100 or immiscible polymer that interacts with incident light primarily by light diffraction and, optionally, dispersion and / or absorption. Diffraction occurs as a result of a difference in the refractive index between the light scattering pigment and the immiscible polymer or structural polymer 100. The light scattering pigments can only diffract, as in the case of titanium dioxide (TiO2), or both can disperse and absorb, as in the case of black iron oxide (PBlk 11). Some examples of light scattering pigments include titanium dioxide (TiO2), ultramarine blue (PB 29), metal oxide particles such as red iron oxide (PR 101), black iron oxide (PB1k 11), chromium hematite green-black (PG 17) or cobalt aluminate (PB 28), aluminum trihydrate (Al (OH) 3), barium sulfate (BaSO4), zinc sulfide (ZnS) or mica.

[0056] When present on a packaging wall, the light scattering pigment is present between about 0.1% by weight and about 5.0% by weight, or between about 0.1% by weight and about 4.0% by weight or between about 0.1 to about 3.0% by weight, or between about 0.2 to about 2.0 weight percent, or between about 0.2 to about 4.0 weight percent, or between about 0.1 to about 0.5 weight percent, or between about 0.1 to about 0.7 weight percent, or between about 0.1 at about 1.0 weight percent, or between about 0.5 to about 2.0 weight percent, of the wall weight.

[0057] In addition, the ratio of polymethylpentene to the light scattering pigment by weight of the wall is between about 5: 1 to about 1: 5, or between about 4: 1 to about 1: 4 or between about 3: 1 to about 1: 3 or between about 2.5: 1 to about 1: 2.5 or between about 2: 1 to about 1: 2 or between about 1.5: 1 to about 1: 1.5 or between about 1.25: 1 to about 1: 1.25, or between about 0.75: 1 to about 3: 1, or between about 0.5: 1 to about 3: 1, between about 0.75: 1 to about 2: 1 or between about 0.5: 1 to about 2: 1. Gonio-Appearance

[0058] The gon-appearance of a surface 200 can be measured with a multi-angle spectrophotometer, such as an X-Rite MA-T12. The color difference of an original light source 210, calculated using CIELAB DECMC, between an initial specular viewing angle 220, a close specular viewing angle 230 and a distant specular viewing angle 240 can be used to quantify the magnitude of the gonion -appearance. The original light source 210 can approach surface 200 at any desired angle. For example, as shown in Figure 2, the light source 210 can approach the surface at an angle of incidence of 45 degrees. In addition, the close specular viewing angle 230 forms an angle with the initial specular viewing angle 220 which is less than the angle formed by the distant specular viewing angle 240 and the initial specular viewing angle 220. For example, as shown in In Figure 2, the close specular viewing angle 230 can be 15 degrees and the distant specular viewing angle 240 can be 110 degrees. Dye

[0059] Instant compositions optionally include at least one dye. The dye can absorb a first range of light wavelengths, contained in a spectrum of light wavelengths between about 200 nm and about 1200 nm. Suitable dyes include any of the organic dyes, organic pigments, inorganic dyes and inorganic pigments that are commonly used as dyes in polymer applications. Examples of such dyes include the following dyes of the respective colors, to be shown below. In the following, the designation "CI" means color index.

[0060] A black dye includes, for example, carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, non-magnetic ferrite, magnetic ferrite and magnetite.

[0061] A yellow pigment includes, for example, CI yellow pigment 13, CI yellow pigment 14, CI pigment yellow 17, CI pigment yellow 74, CI pigment yellow 93, CI pigment yellow 155, CI pigment yellow 180, CI pigment yellow 180 and CI yellow pigment 185.

[0062] An orange dye includes, for example, chromium yellow red, molybdenum orange, permanent GTR orange, pyrazolone orange, volcano orange, indathrene RK bright orange, benzidine G orange, GK indatrene bright orange, CI orange pigment 31, CI orange pigment 43.

[0063] A red dye includes, for example, CI pigment red 52, CI pigment red 53, CI pigment red 19, CI pigment red 48: 1, CI pigment red 48: 2, CI pigment red 48: 2, CI pigment red 48: 3, CI pigment red 57: 1, CI pigment red 122, CI pigment red 150 and CI pigment red 184.

[0064] A purple dye includes, for example, C.I. pigment violet 23, purple manganese, rapid violet B and methyl violet varnish.

[0065] A blue dye includes, for example, C.I.blue pigment 15, C.I.blue pigment 15: 2, C.I.blue pigment 15: 3, C.I.blue pigment 15: 4, C.I.blue pigment 16 and C.I.blue pigment 60.

[0066] A green dye includes, for example, green chromium, chromium oxide, green pigment B, micalite green varnish, final green yellow G and C.I.green pigment 7.

[0067] A white dye includes a compound, for example, zinc powder, titanium oxide, white antimony and zinc sulfide.

[0068] The dye can include non-traditional pigments. Examples of these non-traditional also called "effect pigments" are: thermochromic pigments, fluorescent pigments, pearlescent pigments, metallic pigments and combinations thereof. These "effect pigments" are compounds separated from the light scattering pigment.

[0069] The dyes can be used alone or two or more of them of different colors can be used together. A plurality of dyes from an identical color system can also be used together. The ratio of the optional dye to structural polymer 100 is not particularly restricted and can be suitably selected within a wide range according to various conditions, such as the type of structural polymer 100 or the characteristics necessary for the desired color to be achieved. As an example, the ratio of the dye used to structural polymer 100 may preferably be 0.0001 parts by weight or 5 parts by weight or less and, more preferably, 0.0004 parts by weight or more and 5 parts by weight or less based on 100 parts by weight of structural polymer 100. L * value

[0070] In the CIELAB L *, a *, b * color space, the L * value greater than about 80 looks bright. In the present invention, the L * value of the composition after orientation can be between about: 70, 75, 80, 85, 90, 95 or 97 to 99.5, which is normally the maximum. Before orienting the polymethylpentene, the L * value may have a lower range. In preferred embodiments, white packaging walls have an L * value greater than 80 or greater than 85 or greater than 90 or greater than 95. Light barrier

[0071] The barrier against light is a quality that characterizes the prevention of light from traveling through a sample over several wavelengths of light. The light barrier can be measured as the average amount of light prevented from passing through a sample from 400 nm to 700 nm. The light barrier can also be measured as an optical density. The optical density is the log 10 of the proportion of light that passes through a sample. This is beneficial for measuring samples with a very high light barrier. For example, an optical density of 3 means that 99.9% of the light is prevented from passing. In the present invention, the wall can prevent: 75%, 80%, 85%, 90%, 95%, 97%, 98%, 99% or 99.5% to 100% of light from passing through the wall. Spectrum of Light Wavelengths

[0072] The relevant light spectrum that the described container blocks is not restricted to the visible light spectrum. In fact, light in the ultraviolet and infrared spectrum can cause unwanted changes in products. In non-limiting examples, the spectrum of wavelengths of light blocked by the combination of structural polymer 100 and polymethylpentene, the light scattering pigment and / or the dye includes: between about 200 nm to about 1200 nm; between about 250 nm to about 1000 nm; between about 300 nm to about 900 nm; between about 350 nm to about 800 nm; between about 400 nm to about 700 nm; between about 350 nm to about 600 nm; and between 350 nm to 550 nm. Barrier Properties

[0073] The packaging may provide other barrier properties for, for example, moisture, oxygen, microbes, grease or carbon dioxide. In fact, in certain embodiments, the packaging wall may include oxygen scavengers. Examples of such oxygen scavengers are: polybutadiene-PET block copolymers with transition metal salts used as a catalyst; polyalkylene glycols, their copolymers and mixtures; and co-polyethers. Density

[0074] Polymethylpentene has a particular advantage of having a low density. Low density reduces the total weight of the part and generates cost savings. For example, polymethylpentene has a density of 0.83 g / cm3, while polyester terephthalate has a density of 1.39 g / cm3. By incorporating 5 parts of polymethylpentene with 100 parts of polyester terephthalate, for example, the density of the composite is reduced by 3.1%. Since many plastic articles are manufactured in a specific volume, this results in less article weight and less polymer consumption. Pigments for light scattering, such as TiO 2, BaSO4 or ZnS have very high density which, when incorporated into a structural polymer, can lead to an increase in the weight of the article. For example, incorporating 5 parts of TiO2, the density of the composite increases by 3.2%. Instead, using a combination of 5 parts of polymethylpentene and 5 parts of TiO2, the total weight of, for example, a container is equivalent to that of a PET container. Packaging Items

[0075] The white light blocking compositions described here can be used to manufacture packaging articles in various shapes. Suitable articles include, but are not limited to, flexible films, flexible bags, bags, semi-rigid and rigid containers, such as bottles (e.g. PET bottles), trays and containers.

[0076] Typical flexible films and bags include those used to pack various food items and may consist of one or a multiplicity of layers to form the overall film or pouch-like packaging material. The white light-blocking composition of the present invention can be used in one, some or all of the layers of this packaging material.

[0077] Typical rigid or semi-rigid articles include plastic, paper or cardboard containers, such as those used for milk, juices, soft drinks, alcohol, as well as thermoformed trays or cups, which usually have a thickness in the range between about 100 µm at about 1000 µm. The walls of such articles may comprise one or more layers of materials. The articles may also take the form of a bottle or can, or a flat iron, cap, flat iron or cap coating, plastisol or seal. The white light blocking composition of the present invention can be used as an integral layer or a portion of or as an outer or inner coating or covering of the formed semi-rigid or rigid packaging article. As a coating, the composition that blocks white light can be extruded as a film together with the rigid article itself, in, for example, a co-extrusion coating process, extrusion coating or extrusion lamination process, to form the in situ coating during article production; or, alternatively, it can be adhered by heat and / or pressure, by adhesive or by any other method suitable to an external surface of the article after the article has been produced.

[0078] In a non-limiting mode, a container includes a bottom connected to a side wall, defining an interior space. The container can be formed by the composition that blocks white light. In such an embodiment, the container may also include a top that contains an opening connected to the side wall with optionally an opening seal. A light sensitive product,

for example, a food product, such as milk, can be placed inside the interior. The composition that blocks white light may involve all or part of the container or be restricted to opening only. Finally, the container can be resistant to oxygen.

[0079] In a non-limiting embodiment of the present invention, the composition of the present invention (for example, a structural polymer base, polymethylpentene and a pigment for dispersing light and, optionally, another pigment and / or dye) can be used to form a monolayer of a bottle. In another non-limiting embodiment of the present invention, the composition of the present invention can form one or more layers of a multilayer bottle.

[0080] In addition to articles applicable to food and beverage packaging, articles for packaging other products can also benefit from the present invention. Such products include pharmaceutical products, light sensitive medical products, audiovisual films and the like. The labeling purposes of the product may also require that the packaging be bright white in color so that the specific trademark can be printed on the container. Article Walls

[0081] In some embodiments, the invention relates to the use of the compositions described here as a component of a wall that is used in a desired white packaging for light-sensitive materials.

[0082] The wall can be rigid, a flexible sheet or an adhesive film. It can be homogeneous or laminated or coated with other polymers. If it is laminated or coated, the white color and light blocking property may reside in a layer of the wall that alone will not work satisfactorily (for example, it will not be bright enough white). However, if the layer is combined with other white layers that block light, the article may perform satisfactorily (for example, appearing bright white and blocking light).

[0083] The packaging walls of the present invention can be a single layer or a multilayered construction. In some embodiments using multi-layered walls, the outer and inner layers may be structural layers with one or more protective layers that contain the structural layer and the polymethylpentene between them. In some embodiments, the outer and inner layers comprise a polyolefin, a polyester or nylon. In certain embodiments, a single layer design is preferred. This layer can have advantages in simplicity of manufacture and cost. Manufacturing Method

[0084] The present compositions can be made by mixing a structural polymer of polyester (PET, for example) with polymethylpentene, a pigment that disperses light and, optionally, another pigment and / or dye. Such compositions can be made by any method known to those skilled in the art. In certain embodiments, some or all of the light-dispersing pigment and / or dye may exist in the structural base polymer or polymethylpentene prior to mixing. This opacifier or residual dye, for example, may exist as a result of a recovery process (ie recycling). In some embodiments, the structural polymer, polymethylpentene, light-dispersing pigment and other optional pigments and / or dyes are mixed by rotation in a hopper. Other optional ingredients can be added during this mixing process or added to the mixture after mixing mentioned above or to an individual component before the mixing step mentioned above.

[0085] The present composition can also be made by adding each ingredient separately and mixing the ingredients before melting the composition to form an article. In some embodiments, the mixing may be immediately prior to the melting process zone. In other embodiments, one or more ingredients can be pre-mixed in a separate step prior to the assembly of all ingredients.

[0086] The present composition can also be produced from kneading melting. In such a non-limiting embodiment, the structural polyester polymer, polymethylpentene, light-dispersing pigment and the optional dye (and other components, if present) are kneaded to prepare a kneaded resin product. Kneading melting is conducted substantially without the use of an organic solvent, however, small amounts of an organic liquid (including an organic solvent) can be present as a process aid to, for example, control polymer dust. The kneaded polymer composition can optionally contain additives, for example, a release agent such as wax and an additive such as a charge controller. The additives are kneaded together with the structural polyester polymer, polymethylpentene, pigment for the dispersion of light and the optional dye and dispersed in the kneaded polymer composition.

[0087] In another aspect, the invention provides a rigid, semi-rigid, foldable, capped or flexible package or a combination thereof, which comprises a wall as formed from the compositions described herein. Such packages can be formed by methods well known to those skilled in the art.

[0088] Among the techniques that can be used to make articles are general molding, elastic blow molding, extrusion, thermoforming, extrusion blow molding, biaxial orientation and (specifically for multilayer structures) coextrusion and lamination using bonded adhesive layers. The orientation, for example, by stretch blow molding, of the polymer is especially attractive to polyesters due to the known mechanical advantages that result.

[0089] The melting processing zone for the manufacture of the article can be operated under usual conditions effective for the manufacture of the desired articles, such as preforms, bottles, trays and other articles mentioned below. In one embodiment, these conditions are effective for processing the fusion without substantially increasing the fusion IV and are ineffective in promoting transesterification reactions. In some preferred embodiments, suitable operational conditions effective for establishing a physical mixture of structural polymer, polymethylpentene, light dispersion pigment and dye are temperatures in the melt processing zone within a range of about 200 ° C to about 300 ° C in a total cycle time of less than about 6 minutes and typically without the application of vacuum and under a positive pressure ranging from about 0 psig to about 900 psig. In some embodiments, the residence time of the melted product on the thread can vary from about 1 to about 4 minutes.

[0090] Specific articles include preforms, trays, containers and rigid packaging for the packaging of food, beverages, cosmetics, pharmaceuticals and personal care products, where a shiny white packaging is desired and light blocking is required. Examples of beverage containers are bottles for storing beer and juice, and the invention is particularly useful in applications for bottles containing milk or any other beverage where the packaging is intended to be glossy white and the light adversely affects the taste, fragrance and the performance (prevents vitamin degradation) or color of the drink. Rigid packaging includes food trays and lids. Examples of food tray applications include dual supplyable food trays or cold storage trays, both at the base of the container and on the liner (either a thermoformed lid or a film), where the freshness of the food content can deteriorate when exposed to light . The compositions of the present invention are also useful in the manufacture of containers for pharmaceutical products or medical devices. Master Batch

[0091] In another aspect, the present composition can be used as a master batch for mixing with a polymer or a component containing the polymer. In such compositions, the concentration of, for example, polymethylpentene, the pigment for dispersing light and, optionally, another pigment and / or a dye will be higher to allow the final mixed product to have adequate amounts of these components. The master batch can also contain an amount of structural polyester polymer with which the master batch is to be mixed. In other embodiments, the master batch may contain a structural polyester polymer that is compatible with a second structural polymer to which the master batch is to be mixed. In other embodiments, the master batch may contain polymethylpentene and a second functional polymer, one or both of which may be incompatible with the structural polymer. Definitions

[0092] In this application and in the following claims, reference will be made to various expressions, which must be defined to have the following meanings.

[0093] As used here, the expressions "o / a", "um / uma" and the like refer to the singular and the plural, unless the context clearly indicates otherwise. "A bottle", for example, refers to a single bottle or more than one bottle.

[0094] Also as used here, the description of one or more steps of the method does not prevent the presence of additional steps of the method before or after the combined steps mentioned. Additional steps can also be intermediate steps to those described. In addition, it is understood that the registration of the steps or ingredients of the process is a convenient way to identify different activities or ingredients and the registration mentioned can be organized in any sequence.

[0095] When a range of numbers is presented in the application, it is understood that the range includes all integers and their fractions between the declared limits of the range. A number range expressly includes numbers less than the declared extreme points and those between the indicated range. A range from 1 to 3, for example, includes the integers one, two and three, as well as the fractions that reside between those integers.

[0096] As used here, "master batch" refers to a mixture of polymethylpentene, pigment for the dispersion of light and an optional dye and an optional structural polymer, and another optional polymer and other optional additives that will be diluted, typically with at least less additional structural polymer, before forming an article. As such, the concentrations of polymethylpentene, pigment for the dispersion of light and / or dye are higher than in the formed article.

[0097] The following examples are included to demonstrate the preferred embodiments of the invention in relation to the utility of PET-based resin mixed with polymethylpentene and a pigment for the dispersion of light to make glossy white packages. It should be appreciated by those skilled in the art that the techniques disclosed in the examples below represent techniques discovered by the inventors to work well in the practice of the invention and, therefore, can be considered as modes for their practice. However, those skilled in the art must, in light of the present description, appreciate that many changes can be made in the specific modalities that are described and still obtain a similar or similar result without departing from the spirit and scope of the invention.

EXAMPLES

[0098] The following materials are referenced in Table 1 below:

[0099] PMP - polymethylpentene, grade RT-31 from Mitsui Chemicals America, Inc. Counterexample 5 and Example 6 used grade RT-18 from Mitsui Chemicals America, Inc.

[00100] PET - p polyethylene terephthalate, grade PQB-4 from Polyquest, Inc. Polymer bottle grade 0.80 IV.

[00101] PETG - co-polyester modified with glycol, Skygreen K2012 grade from SK Chemicals.

[00102] TiO2 - titanium dioxide, pigment for light dispersion, Cl Pigment White 6, class CR-834 from Tronox Limited, general purpose rutile class.

[00103] PPRO-polypropylene, Primaflex® HP 3500 grade from Plastics Solutions, Inc. molten flow homopolymer 35.

[00104] ZnS - Zinc sulfide, pigment for light dispersion, Cl Pigment White 7, Sachtloth HD-S from Venator.

[00105] PBlk 7 - carbon black, Black Spheres 4350 from Cabot.

[00106] PBlk 11 - Iron oxide black, Cl Pigment Black 11, class Bayferrox 318M from Lanxess.

[00107] SB 104 - Cl Solvent Blue 104, Milliken Keyplast Blue KR grade, non-dispersing light dye.

[00108] TiO2 MB - 65% of TiO2 and 35% of PET were extruded in a 25 mm twin screw extruder in coil at 300 RPM and 250 ° C and cut into pellets.

[00109] ZnS MB - 50% of ZnS and 50% of PET were extruded in a 25mm twin screw extruder in coercion at 300RPM and 250 ° C and cut into pellets.

[00110] SB 104 MB - 10% SB 104 and 89.3% PETG, 0.5% epoxidized soybean oil and 0.2% BNX 1010 stabilizing grade antioxidant were extruded in a 25 mm screw extruder in corrotation at 300RPM and 250 ° C and cut into pellets.

[00111] Examples 6, 7a, 7b, 7c, 7d, 8a, 8b, 8c, 9 and 10 all used a prefabricated master batch. The composition of each master batch is listed in Table 1. All the compositions of the master batch were extruded in a 25 mm twin screw extruder in coil at 300 rpm and cut into pellets. Each master batch was added to the feed throat of the extrusion step of a blow molding process, in the quantity shown in Table 1 below:

Table 1: Master batch samples used in the examples and counterexamples PPRO PMP TiO2 ZnS PBlk 7 PBlk 11 PET PETG Dosage Ex 6 MB 50.00% 50.00% 5.00% Ex 7a MB 99.01% 0.99% 6 , 06% Ex 7b MB 65.00% 0.50% 34.50% 12.00% Ex 7c MB 43.10% 56.04% 0.86% 6.96% Ex 7d MB 43.29% 56, 28% 0.43% 6.93% Ex 8a MB 99.40% 0.60% 10.06% Ex 8b MB 65.00% 1.20% 33.80% 5.00% Ex 8c MB 74.78 % 24.33% 0.90% 6.68% Ex. 9 MB also Ex 10 25.00% 75.00% 3.00% Ex. 10 MB 0.50% 99.50% 4.00%

[00112] For all samples, the additives were mixed in the feed throat of the extrusion step of a blow molding process on a Nissei ASB 50M blow molding machine. The bottles were blown with an axial orientation of 3.3x and a circumferential orientation of 3.3x for a total wall orientation of 10.9x <2>. The final composition of each sample is shown in Table 2 below:

Table 2: Final bottle compositions Name PMP TiO2 PPRO ZnS PBlk 7 PBlk 11 SB 104 PET Ex 1a 6.00% 94.00% Ex 1b 7.80% 92.20% Ex 1c 3.00% 3.90% 93 , 10% Ex 1d 2.40% 3.12% 94.48% Ex 2a 10.00% 90.00% Ex 2b 3.25% 96.75% Ex 2c 1.63% 5.00% 93.38 % Ex 3 1.50% 0.50% 98.00% Ex 4 1.50% 0.25% 98.25% Ex 5 1.50% 0.60% 97.90% Ex 6 2.50% 2 , 50% 95.00% Ex 7a 6.00% 0.06% 93.94% Ex 7b 7.80% 0.06% 92.14% Ex 7c 3.00% 3.90% 0.06% 93 , 04% Ex 7d 3.00% 3.90% 0.03% 93.07% Ex 8a 10.00% 0.06% 89.94% Ex 8b 3.25% 0.06% 96.69% Ex 8c 1.63% 5.00% 0.06% 93.32% Ex 9 0.750% 2.25% 97.00% Ex 10 0.750% 2.25% 0.02% 96.98%

[00113] The above mentioned compositions were subjected to orientation forces and the properties of their appearance were measured. The measurement results are shown in Table 3 below:

Table 3: Measured properties of appearance Barrier to Gonio- Goniocromatics PMP density for Example Light appearance Non-pearly optical L * a * b * Pigment Ex 1a 96.2% 26.8 No 1.24 96.9 0.0 -0, 1 N / A Ex 1b 96.3% 3.7 Yes 1.25 97.1 -0.7 0.8 0: 1 Ex 1c 98.2% 4.0 Yes 1.52 97.7 -0.6 1.1 0.77: 1 Ex 1d 96.7% 4.2 Yes 1.20 97.6 -0.5 0.7 0.77: 1 Ex 2a 90.5% 27.8 No 0.88 96 , 1 0.0 0.1 N / A Ex 2b 90.1% 2.5 Yes 0.82 96.2 -0.8 0.8 N / A Ex 2c 88.5% 4.9 Yes 0.75 96.2 -0.6 0.7 N / A Ex 3 91.0% 9.7 Yes 0.80 97.2 -0.3 0.1 3: 1 Ex 4 90.6% 15.1 No 0 , 79 96.4 -0.4 0.3 6.07: 1 Ex 5 99.9% 32.0 No 3.47 50.9 -7.2 -36.5 1.25: 1 Ex 6 96, 5% 5.9 Yes 1.17 97.1 -0.4 0.4 1: 1 Ex 7a 100.0% 29.9 No 3.44 85.7 0.5 1.2 100: 1 Ex 7b 99 , 7% 4.5 Yes 2.95 87.2 -0.8 -1.6 0: 1 Ex 7c 100.0% 5.4 Yes 5.93 86.6 -0.2 -0.5 0, 76: 1 Ex 7d 99.9% 4.6 Yes 3.00 91.3 -0.1 0.5 0.76: 1 Ex 8a 98.6% 29.3 No 1.73 83.9 0.6 0.7 N / A Ex 8b 99.0% 4.0 Yes 2.08 81.6 -0.8 -2.1 N / A Ex 8c 99.2% 7.2 Yes 2.07 80.9 0 , 2 -0.3 N / A Ex 9 91.5% 2.9 Yes 1.13 96.1 0 , 2 -0.3 1: 3 Ex 10 100.0% 5.9 Yes 3.80 69.0 -0.5 -1.6 1: 3 Examples 1a, 1b, 1c, 1d

[00114] Ex 1a, 1b, 1c and 1d show that there is synergy when an oriented wall of a package combines PMP and a pigment for the dispersion of light. Ex. 1a, which uses only PMP, has a gonioparent appearance and 96.2% light barrier. Ex 1b, which uses only one pigment for light scattering, requires a very high level of masterbatch to achieve the same 96.3% light barrier. By using half the contribution of the light barrier of Ex 1a and Ex 1b, one skilled in the art can anticipate the same performance as the light barrier. However, Ex 1c shows that the light barrier is improved while maintaining a goniochromatic appearance. Ex 1d further illustrated the synergy, reducing the total amount of PMP and the pigment for light dispersion by 20%,

while still matching the Ex 1a and Ex 1b light barrier and maintaining a goniochromatic appearance. Counterexamples 2a, 2b, 2c

[00115] Ex 2a, Ex 2b and Ex 2c show that there is no synergy when an oriented packaging wall combines a different olefin polymer and a light scattering pigment. Ex 2a, which uses PPRO, requires a very high charge level and still cannot reach a light barrier similar to that of Ex 1. Ex 2b, which uses only one pigment for light scattering, corresponds to the barrier for light dispersion of Ex 2a. Using half the contribution of the light barrier of Ex 1a and Ex 1b, the one skilled in the art would anticipate the same performance as the light barrier. However, the Ex 2c shows that the light barrier is slightly worse than that of Ex 2a and Ex 2b. Example 3 and Counterexample 4

[00116] Example 3 and Counterexample 4 show that a ratio of PMP to pigment for light scattering of about 3: 1 results in an appearance that is goniochromatic and maintains color through various viewing angles. However, increasing this ratio of PMP to light scattering pigment to about 6: 1 results in a gonio-apparent appearance and no longer maintains color through multiple viewing angles.

[00117] Counterexample 5

[00118] Counterexample 5 shows that the use of a pigment that does not disperse light does not provide a goniochromatic appearance. The added dye should be a light-dispersing pigment, not an absorbent dye. Example 6

[00119] Example 6 shows that other pigments for light scattering can be used, in the case of Ex 6, Cl White pigment 7, zinc sulfide.

Examples 7a to 7d

[00120] Ex 7a, 7b and 7c show that Ex 7a, 7b and 7c use the same structural polymer, PMP and pigment for light scattering as in Ex 1a, Ex 1b and Ex 1c, but with the addition of 0.060% of PBlk 11 in the final composition. Since the light barrier is very high, the synergy in the light barrier is measured using the optical density. Ex 7d shows that, due to the synergy between PMP and TiO2, the same barrier against light can be achieved, but with a reduced amount of PBlk 11, producing a higher L * and a brighter white, while maintaining a goniochromatic appearance. Counterexamples 8a to 8c

[00121] Ex 8a, Ex 8b and Ex 8c use the same structural polymer, PPRO and pigment for light dispersion as Ex 2a, Ex 2b and Ex 2c, but with the addition of 0.060% PBlk 11 to the final composition. As there is no synergy between PPRO and TiO2, the L * appearance of Ex 7c is less than Ex 8a and Ex 8b. Examples 9 and 10

[00122] Ex 9 and 10 show that there is synergy when an oriented packaging wall combines PMP and a pigment for light scattering. Ex 9, which uses PMP and TiO2, has a gonioparent appearance and a light barrier of 91.5%. The Ex 10 uses PMP, TiO2 and carbon black (PBlk 7) and also has a gonioparent appearance and blocks all light.

[00123] Although illustrated and described above with reference to certain specific embodiments, the present invention is not intended, however, to be limited to the details shown. Instead, various modifications can be made to the details within the scope and scope of the claims equivalents and without departing from the spirit of the invention. It is expressly intended, for example, that all ranges widely described in this document include in their scope all the narrowest ranges that fall within the broadest ranges.

It is also expressly intended that the steps in the methods of using the various compositions disclosed above are not restricted to any specific order.

Claims (20)

1. Packaging item, characterized by the fact that it comprises: a polyester; between about 0.2 to about 4.0 weight percent of polymethylpentene (PMP); and between about 0.1 to about 5.0 weight percent of a light scattering pigment, wherein the ratio of PMP to light scattering pigment is between about 5: 1 to about 1: 5 and where the wall is goniochromatic. 2. Packing article according to claim 1, characterized by the fact that the wall has a gonium-appearance of less than 10 units, measured as DECMC with an incident light source at 45 ° C between 15 ° reflection close specular and 110 ° C of distant specular reflection. 3. Packaging article according to claim 1, characterized by the fact that the polyester is selected from the group consisting of: polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polylactic acid (PLA), terephthalate poly trimethylene (PTT), polyethylene naphthalate (PEN), polyethylene furanoate (PEF), polycyclohexylene dimethylene terephtate (PCT), sulfonated polyesters, polycaprolactone (PCL), polyhydroxyalkanoate (PHA) and copolymers and combinations thereof . 4. Article for packaging, according to claim 1, characterized by the fact that the polyester is PET. 5. Packaging article according to claim 1, characterized by the fact that the light scattering pigment is selected from titanium dioxide (TiO2), metal oxide particles, barium sulfate (BaSO4) and zinc sulfide (ZnS). 6. Packing article according to claim 5, characterized by the fact that the pigment for light scattering is titanium dioxide (TiO2). 7. Packaging article according to claim 1, characterized by the fact that the wall has a light barrier, for light with wavelengths ranging from about 400 nm to about 700 nm, greater than about 90%. 8. Packing article according to claim 1, characterized by the fact that the wall has an L * value according to the CIELAB color space greater than about 75. 9. Article for packaging, according to claim 1, characterized by the fact that the wall is a monolayer wall of the container. 10. Packaging article according to claim 1, characterized by the fact that the wall is an external wall of the packaging article. 11. Article for packaging, according to claim 1, characterized by the fact that the layer further comprises a second pigment or dye 12. Packaging article according to claim 11, characterized by the fact that the second pigment or dye comprises a dye, a thermochromatic pigment, a fluorescent pigment, a pearly pigment, a metallic pigment and combinations thereof. 13. Packaging article according to claim 1, characterized by the fact that the polyester comprises polyethylene terephthalate (PET), the wall has a value of L *, according to the CIELAB color scale, greater than 75 and the wall has a light barrier, for light with wavelengths ranging from about 400 nm to 700 nm, greater than about 90 percent. 14. Packaging article according to claim 1, characterized by the fact that the polyester is polyethylene terephthalate (PET), PMP in the layer is present in an amount between about 0.2 to about 3.0 percent by weight, the pigment for light dispersion in the layer is titanium dioxide present in an amount between about 0.2 to about 4.0 percent by weight and the ratio of PMP to titanium dioxide in the layer is about from 3: 1 to 1: 3. 15. Packaging article according to claim 14, characterized by the fact that the wall has a value of L *, according to the CIELAB color space, greater than about 80, and the wall has a barrier against light, for light with wavelengths ranging from about 400 nm to 700 nm, greater than about 98%. 16. Article for packaging, according to claim 1, characterized by the fact that it also comprises a bottom connected with the wall, in which the bottom and the wall at least partially define an interior space. 17. Method of producing a wall of an article for packaging, characterized by the fact that it comprises: obtaining a composition that comprises a mixture of a polyester, polymethylpentene (PMP) and a pigment for the dispersion of light, in which the PMP comprises about from 0.2 to about 4.0 weight percent of the mixture, the light dispersion pigment comprises about 0.1 to about 5.0 weight percent of the mixture, and the ratio of PMP to the dispersion pigment of light in the mixture is about 5: 1 to about 1: 5; and subjecting the composition to an orientation stress to produce the packaging article wall where the wall is goniochromatic. 18. Method according to claim 17, characterized by the fact that the density of the composition before being subjected to orientation stress is equal to or less than the density of the polyester. 19. Method according to claim 17, characterized by the fact that the density of the composition after being subjected to orientation stress is equal to or less than the density of the polyester. 20. Method, according to claim 17, characterized by the fact that orientation stress is selected from: blow molding, uniaxial or biaxial orientation of the sheet, thermoforming or fiber spinning.